test_ .pyPup
Don’t just test it.
Prove it.
Pup turns your unit tests into proven guarantees.
Never miss an edge case again.
›pup check safe_bounds.py
VERIFIED100% guaranteed for every possible input.
One test to rule them all.
Test infinite possibilities, all at once.
One test. Every possible input.
Proved across the whole codebase.
Meet Supertests.
A unit test checks examples. A supertest defines how your software must behave for every possible input.
1
from schematic import *55
@supertest56
def reversing_twice_restores_text(text: str):57
backward = reverse(text)58
forward = reverse(backward)59
assert forward == text- 1 Declare a supertest
Adding
@supertestturns a regular test into a supertest. - 2 Inputs represent every possible case
The input
textcovers every possible string, not just a few examples. - 3 Assert as usual
Assert or throw an exception just as you would in a regular unit test. Pup handles the rest.
See Pup in action
From supertest to certainty.
Pup is a developer CLI that checks supertests against exact commits. It follows each check live, surfaces problems with reproducible evidence, and helps you fix and recheck the affected behavior.
Pup
supertest-python
mainRun pup check supertests/normalize_spaces.py. The same live view changes from checking to fail for normalizing_twice_changes_nothing. The counterexample is a followed by three spaces and b: the first call leaves two spaces, and the second leaves one. Run pup fix --check 1 to review the patch, type y, and press Enter to apply it. The changes are uncommitted. Run pup check --problems, type y and press Enter to include the changes, and follow the checking progress until the result is pass.
Bugs were a way of life.
No longer.
Give Pup the behavior your software must preserve. Get a verified guarantee, or the exact input that breaks it.
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